The aim of this study was to examine the physical properties of margarines prepared from oleogels with binary mixtures of candelilla wax (CDW) and beeswax (BW) in soybean oil. Some of the margarines ...made from oleogels with mixtures of CDW and BW had higher firmness than those made with one wax. For example, a 3% wax margarine made with 25% CDW and 75% BW had significantly higher firmness (0.97 N) than those with 100% CDW (0.59 N) and with 100% BW (0.11 N). Differential scanning calorimetry (DSC) and solid fat content (SFC) analyses revealed eutectic melting properties for binary wax margarines, which may be desirable since wax oleogel‐based margarines often have higher melting points than conventional margarines. For example, the major melting point of 3% wax margarine made with 50% CDW and 50% BW was 43.85 °C, while for margarines made with 100% CDW or 100% BW, the melting points were at 46.00% and 47.61 °C, respectively. SFC was lowest for margarines with 50 or 75% BW; for example, 3% wax margarine with 25% CDW and 75% BW had 0.72% SFC at 40 °C while those with 100% CDW and 100% BW had 1.19 and 1.13% SFC, respectively. However, dropping point constantly decreased with increasing BW ratios. This study demonstrated that by mixing two waxes, the firmness of oleogel‐based margarines could be increased, and the melting point could be tailored by the ratio of two waxes.
Practical Application
This study demonstrated that firmness and melting properties of margarines prepared from wax‐oleogels can be improved by mixing two waxes, making their practical application more feasible. Firmness of margarines prepared with oleogels of binary mixtures of candelilla wax and beeswax were higher than those with pure waxes. The melting point of wax oleogel‐based margarines was decreased by use of binary mixtures of candelilla wax and beeswax.
Antioxidant activity of bicarbonates and carbonates including NaHCO3, Na2CO3, KHCO3, and K2CO3 was evaluated in soybean oil (SBO) at 180°C. KHCO3 and K2CO3 had stronger activity than NaHCO3 and ...Na2CO3. KHCO3 (5.5 mEq/L, 0.060 wt.%) and K2CO3 (5.5 mEq/L, 0.041 wt.%) were more effective than 0.02 wt.% tert‐butylhydroquinone (TBHQ) in preventing oxidation of SBO. While the antioxidant activity of KHCO3 and K2CO3 increased with increasing their concentrations up to 5.5 mEq/L, it decreased at 11 mEq/L. KHCO3 and K2CO3 were also effective in preventing oxidation of other vegetable oils including avocado, canola, corn, high oleic soybean, and olive oils. Correlation tests conducted with the results from the six oils showed that KHCO3 and K2CO3 had weak to moderate positive correlations with γ‐ and δ‐tocopherols. In a separate study in stripped SBO, it was found that KHCO3 had a synergistic effect with α‐tocopherol, but not with γ‐ and δ‐tocopherols. KHCO3 had additive or synergistic effect with rosemary extract, epigallocatechin gallate, ascorbic acid, and ascorbyl palmitate. Antioxidant activity of KHCO3 was confirmed in frying of potato cubes in SBO and canola oil. Although more studies should be conducted for better understanding of the mechanisms and factors affecting the antioxidant activity of bicarbonates and carbonates, this study demonstrated that they could serve as antioxidants or co‐antioxidants of other antioxidants in frying.
Practical Application
Inorganic salts including NaHCO3, KHCO3, Na2CO3, and K2CO3 hadstrong antioxidant activity in vegetable oils at frying temperatures when they wereadded as powder. Antioxidant activity of 0.06 wt.% KHCO3 was higherthan that of 0.02 wt.% TBHQ in soybean oil and canola oil during frying potato. KHCO3 had additive orsynergistic effect with rosemary extract, epigallocatechin gallate, ascorbicacid, and ascorbyl palmitate indicating that these inorganic salts can be usedas co‐antioxidants to enhance the antioxidant activity of existing antioxidantswhile they can be used alone as well.
BACKGROUND
Oxidized feed lipids have been shown to have detrimental effects on food animal growth and metabolism. The present study aimed to measure classes of lipid oxidation products (LOP) in ...feed‐grade oils at temperatures representing production and storage conditions.
RESULTS
There were significant oil type × time interactions in the accumulation of primary and secondary LOP. At 22.5 °C, peroxide value (PV), a marker for the primary phase of lipid oxidation, increased most in fish oil (FO), followed by tallow (TL), soybean oil (SO), linseed oil (LO) and modified algae oil (MAO), whereas palm oil (PO) showed no appreciable increase in PV. Secondary LOP, such as p‐anisidine value, hexanal, 2,4,‐decadienal, polymerized triacylglycerols and total polar compounds, increased only in FO. At 45 °C, FO and SO produced both primary and secondary LOP, whereas MAO, PO and TL had slower rates of PV increase and no secondary LOP. At 90 °C and 180 °C, all oils except for FO accumulated both primary and secondary LOP.
Conclusions
Higher polyunsaturated fatty acid:saturated fatty acid oils and higher temperatures produced greater quantities of primary and secondary LOP. However, unrefined TL was more prone to oxidation at 22.5 °C than predicted, whereas LO was more stable than predicted, indicating that pro‐oxidant and antioxidant compounds can markedly influence the rate of oxidation. Measuring both primary and secondary LOP will provide better information about the oxidative status of feed oils and provide better information about which classes of LOP are responsible for detrimental health effects in animals. Published 2020. This article is a U.S. Government work and is in the public domain in the USA.
It was previously reported that sunflower wax (SW) had high potential as an organogelator for soybean oil–based margarine and spread products. In this study, 12 other vegetable oils were evaluated in ...a margarine formulation to test feasibility of utilization of SW as an alternative to solid fats in margarine and spread products containing these oils. The minimum quantity of SW required to form a gel with these oils ranged from 0.3% to 1.0% (wt.). Organogels were prepared from the vegetable oils with 3%, 5% and 7% SW and were tested for firmness as well as melting behaviors using differential scanning calorimetry. These organogels were also incorporated into a margarine formulation. All of the vegetable oil organogels produced relatively firm margarines. The margarines prepared from organogels containing 3% (wt.) SW had greater firmness than commercial spreads, whereas margarines made from 7% SW were softer than commercial stick margarines. However, dropping points of the margarine samples were higher than those of commercial spread and margarine products. Margarine firmness was modestly inversely correlated with the amount of polar compounds in the oils and did not correlate with fatty acid compositions. This study demonstrates the feasibility of using a number of healthy vegetable oils rich in polyunsaturated fatty acids to make healthy margarine and spread products by utilizing SW as an organogelator.
The aim of this study is to evaluate the oleogel (or organogel) technology as a new method to prevent oxidation of fish oil by immobilizing oil and to provide useful information on oxidation of ...oleogels for their application in actual food products. Four different natural waxes, rice bran wax, sunflower wax, candelilla wax, and beeswax are used to prepare fish oil oleogels. Peroxide value, conjugated diene value, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) are measured after storing oleogels at 35 and 50 °C, respectively. All 3% wax‐fish oil oleogels shows slower oxidation than the bulk fish oil at 35 °C. Beeswax is not as effective as other waxes during storage at 50 °C due to its lower melting point. The color penetration measurement method is developed as a convenient method to predict the oxidation rate of oleogel. Cooling oleogel at a faster rate can significantly reduce the oxidation rate of the oleogel. A larger amount of wax is not recommended to increase the protective effect, which can give a negative effect due to the prooxidant activity of wax. The oleogel technology may be applied to reduce oxidation of food products and nutritional supplements containing omega‐3 oil.
Practical Application: This study clearly shows that the oleogel technology can be used to prevent oil oxidation by immobilizing oil in food products. This technology can be used for commercial products such as fish oil supplements to prevent oil oxidation during production, transportation, and storage. The information presented in this study can also be used for new omega‐3 oil fortified food products such as margarine, spreads, shortening, cookies, and other related products. The oleogel technology can be easily applied as a drop‐in method. Natural waxes used as oleogelator are inexpensive and widely available, and most of them are already used in many food products.
Peroxide value of 3% wax‐fish oil oleogels stored at 35 °C for 7 days.
Peroxide value of 3% wax‐fish oil oleogels stored at 35 °C for 7 days.
Natural peanut butter was stabilized with 1.0%–2.0% (w/w) beeswax (BW), candelilla wax (CLW), rice bran wax (RBW), or sunflower wax (SFW). The appearance, spreadability, mouthfeel, and flavor ...attributes of these samples were evaluated by a trained sensory panel using commercial stabilized peanut butter and a sample stabilized with hydrogenated cottonseed oil as references. The waxes and their blend ratio significantly (p < 0.05) influenced appearance, spreadability, firmness, mouthfeel, and flavor attributes. Samples with 1.5%–2.0% CLW, or 1.0%–1.5% RBW had the fewest differences in appearance and texture from the reference and commercial samples. However, an off‐flavor was attributed to 1.5% or higher CLW. Samples stabilized with BW or with 1.0%–1.5% RBW had the fewest difference in flavor compared to the reference sample. Overall, samples stabilized with 1.0%–1.5% RBW scored closest to the commercial and reference samples. The response of CLW, RBW, and SFW (which was only evaluated for appearance and spreadability) indicates that amounts of these waxes could be tailored in different products to achieve a product with desirable texture and flavor as well as stability to oil loss.
Practical Application
This research provides information that could be used by food companies that make seed or nut butters as spreads or as ingredients for use in foods. It shows the impact of the use of four types of waxes as stabilizers, at commercially relevant levels (< 3.0%), and at levels previously shown to be effective for stabilization, on the firmness, spreadability, and other texture and flavor attributes, and thus provides a starting point for optimization for commercial product specifications.
Some amino acids have strong antioxidant activity in frying oil. This study aimed to obtain further information including antioxidant activity at different concentrations and interactions with ...rosemary extract, green tea extract, and ascorbic acid. Antioxidant activity of arginine, cysteine, lysine, methionine, and tryptophan was examined by increasing the concentration in soybean oil (SBO) at 180 °C within the concentration range of 0 to 15 mM. These amino acids showed increased activity with increasing concentration without showing prooxidant activity at the given concentration range. Addition of 15 mM methionine did not inhibit the prooxidant activity of α‐tocopherol at high concentrations in SBO while it significantly increased the activity at each concentration of α‐tocopherol. Methionine showed an additive effect with a commercial rosemary extract while lysine had an antagonistic interaction in SBO at the total concentration of 5.5 mM. Mixtures of green tea extract and methionine did not show better activity than methionine alone in SBO and stripped SBO. (‐)‐Epigallocatechin gallate, the major active component in green tea, showed a synergistic effect with methionine in stripped SBO but there was no significant interaction effect in SBO. Although ascorbic acid had a synergistic effect with methionine in stripped SBO, it showed a significant antagonistic effect in SBO. Methionine had strong antioxidant activity in six other vegetable oils showing a moderate correlation (R2 = 0.45 to 0.52) with the ratio of unsaturated fatty acids to saturated fatty acids indicating the effectiveness may be related to the fatty acid composition of oil.
Practical Application
Some amino acid such as methionine and lysine showed stronger antioxidant activity than the leading commercial natural antioxidant, rosemary extract. These amino acids showed great potential as a natural antioxidant in frying. The price of food‐grade L‐methionine is generally lower than rosemary extract and green tea extract. This paper provides information on the concentration effect and interactions with currently used antioxidants such as tocopherols, rosemary extract, green tea extract, and ascorbic acid.
Organogels obtained from plant wax and soybean oil were tested for their suitability for incorporation into margarine. Sunflower wax, rice bran wax and candelilla wax were evaluated. Candelilla wax ...showed phase separation after making the emulsion with the formulation used in this study. Rice bran wax showed relatively good firmness with the organogel, but dramatically lowered firmness for a margarine sample. Sunflower wax showed the greatest firmness for organogel and the margarine samples among the three plant waxes tested in this study. Firmness of the margarine containing 2–6 % sunflower wax in soybean oil was similar to that of margarine containing 18–30 % hydrogenated soybean oil in soybean oil. The firmness of commercial spread could be achieved with about 2 % sunflower wax and that of commercial margarine could be achieved with about 10 % of sunflower wax in the margarine formulation. Dropping point, DSC and solid fat content of the new margarine containing 2–6 % sunflower wax showed a higher melting point than commercial margarine and spreads.
Phytosterols (plant sterols) occur in the cells of all plants. They are important structural components that stabilize the biological membranes of plants. Sterols can occur in the “free” unbound form ...or they can be covalently bound via an ester or glycosidic bond. Since our previous 2002 review on phytosterols and phytosterol conjugates, phytosterol glucosides have been found to be important structural components in the lipid rafts of the plasma membrane of plant cells, where they are thought to be essential to the function of plasma membrane enzymes and perhaps other proteins. Phytosterols also serve as precursors in the synthesis of important bioactive compounds such as steroidal saponins, steroidal glycoalkaloids, phytoecdysteroids, and brassinosteroids. Methods for the analysis of phytosterols range from traditional gas chromatography of free phytosterols to modern sophisticated forms of mass spectrometry which have been used for the new field of sterol lipidomics, sometimes called “sterolomics.” Phytosterol-enriched functional foods first appeared about twenty years ago and many clinical studies have confirmed the low density lipoprotein (LDL) cholesterol-lowering properties of various types of phytosterols. In recent years additional clinical studies and more than ten important meta-analyses have provided insights to better understand the cholesterol-lowering and other biological effects of plant sterols.
Although it is important to understand the factors affecting the physical properties of oleogels for their application in food products, the effects of the kind of oils and components in them are not ...well understood. Previous studies on the effects of unsaturation and polar compounds of oils on the properties of oleogels reported inconsistent results, presumably, due to different gelling agents, experimental conditions, and different amounts of minor components in oils. In this study, a systematic study was conducted with 12 vegetable oils with and without polar compounds to understand these effects on the properties of 3% and 7% sunflower wax (SW)‐oleogels. In general, oils with higher unsaturation produced oleogels with lower gel strength. Polar compounds in oil negatively affected the gel strength. Melting and crystallization temperatures increased with increasing unsaturation of oil. The platelet shape of SW crystals was almost identical, regardless of the kind of oil. Solid wax content values were similar across the oleogel samples with 12 different oils. This study enlightens several factors affecting the physical properties of SW‐oleogels.
Practical Application: This study provides information about the effects of unsaturation of oil and polar compounds in oil on firmness and melting properties of sunflower wax (SW)‐based oleogels. It was found that the firmness of SW‐oleogel can be significantly different (up to 65%) depending on vegetable oils used, and it decreased with increasing unsaturation of oil. It was also found that the firmness of the oleogel can be increased by up to 36% by removing polar compounds in oil. Solid wax content (SWC) of oleogels did show meaningful correlations with the firmness of SW‐oleogels. All the oleogels examined in this study had very similar shapes and sizes of SW crystals. For practical application, the unsaturation of oil and the polar compound content have to be considered when designing oleogels with desired textural properties.
Graphical : The firmness of 3% sunflower wax‐oleogels with 12 different vegetable oils had negative correlations with the iodine value of oils (r = −0.60 with unstripped oils and −0.39 with stripped oils).